182 research outputs found

    Multiphonon effects in paraelectric relaxations

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    A theory is presented for the temperature dependence of the relaxation rate of paraelectric impurities in alkali-halides. The impurity is regarded as a two-level system coupled linearly to a phonon field. The relaxation rate is evaluated for arbitrary number of phonons, using a Debye spectrum for the lattice. The results agree well with experiments by Kapphan and Luty for relaxation of OH- impurities in RbBr.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/33721/1/0000233.pd

    Attachment of an electron-hole droplet to a donor

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    The attachment of an electron-hole droplet to a donor in Ge is considered using the density-functional method. We find the heat of solution of a donor in a droplet to be about 7 meV, and the electron density at the donor to be 32 times the carrier density in the droplet far from the donor. Effects on droplet pinning and recombination are discussed.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/22582/1/0000130.pd

    Ground state energy of small electron-hole drops

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    The ground state energy of small electron-hole drops is calculated for droplets ranging in size from 10 to 10,000 pairs. A new value for the bending energy of 1.1 x 10-10 erg/cm is derived. We also give a simple highly accurate formula for the total energy per pair. The surface energy is extracted from the total energy and found to agree well with a previous self-consistent calculation. The density at the center of the drop remains essentially constant over the entire range of N, indicating that the drop is not dramatically compressed by the surface tension.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/23730/1/0000702.pd

    Autologous Stem Cell Transplant is Feasible in Very Elderly Patients with Lymphoma and Limited Comorbidity

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    In patients with recurrent Hodgkin or non-Hodgkin\u27s lymphoma, autologous stem cell transplantation (ASCT) can offer potential for cure or long-term remission. Because of potential toxicity, elderly patients are usually not considered candidates, but data regarding tolerability and efficacy in this group are lacking. The transplant database at Weill Cornell Medical College was reviewed to identify patients with lymphoma undergoing ASCT at age 69 or greater. Clinical data and comorbidities were correlated with outcome. Twenty-one patients were identified. Sixteen of 19 evaluable patients (76%) achieved complete remission following ASCT, while 2 patients died before response assessment. Median progression-free survival following ASCT was 8 months and median overall survival was 18 months. Age was not predictive of overall survival, but patients 75 and older had inferior progression-free survival compared to younger patients. High-risk status by hematopoietic stem cell transplant comorbidity index (HCT-CI) was associated with short overall survival and high transplant-related mortality. ASCT is feasible and of potential benefit in selected elderly lymphoma patients. Consideration of comorbidities, rather than age alone, may allow selection of patients likely to tolerate and benefit from ASCT

    Autologous Stem Cell Transplant is Feasible in Very Elderly Patients with Lymphoma and Limited Comorbidity

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    In patients with recurrent Hodgkin or non-Hodgkin\u27s lymphoma, autologous stem cell transplantation (ASCT) can offer potential for cure or long-term remission. Because of potential toxicity, elderly patients are usually not considered candidates, but data regarding tolerability and efficacy in this group are lacking. The transplant database at Weill Cornell Medical College was reviewed to identify patients with lymphoma undergoing ASCT at age 69 or greater. Clinical data and comorbidities were correlated with outcome. Twenty-one patients were identified. Sixteen of 19 evaluable patients (76%) achieved complete remission following ASCT, while 2 patients died before response assessment. Median progression-free survival following ASCT was 8 months and median overall survival was 18 months. Age was not predictive of overall survival, but patients 75 and older had inferior progression-free survival compared to younger patients. High-risk status by hematopoietic stem cell transplant comorbidity index (HCT-CI) was associated with short overall survival and high transplant-related mortality. ASCT is feasible and of potential benefit in selected elderly lymphoma patients. Consideration of comorbidities, rather than age alone, may allow selection of patients likely to tolerate and benefit from ASCT

    Intravesical rAd-IFNα/Syn3 for Patients With High-Grade, Bacillus Calmette-Guerin-Refractory or Relapsed Non-Muscle-Invasive Bladder Cancer: A Phase II Randomized Study.

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    Purpose Many patients with high-risk non-muscle-invasive bladder cancer (NMIBC) are either refractory to bacillus Calmette-Guerin (BCG) treatment or may experience disease relapse. We assessed the efficacy and safety of recombinant adenovirus interferon alfa with Syn3 (rAd-IFNα/Syn3), a replication-deficient recombinant adenovirus gene transfer vector, for patients with high-grade (HG) BCG-refractory or relapsed NMIBC. Methods In this open-label, multicenter (n = 13), parallel-arm, phase II study ( ClinicalTrials.gov identifier: NCT01687244), 43 patients with HG BCG-refractory or relapsed NMIBC received intravesical rAd-IFNα/Syn3 (randomly assigned 1:1 to 1 × 10(11) viral particles (vp)/mL or 3 × 10(11) vp/mL). Patients who responded at months 3, 6, and 9 were retreated at months 4, 7, and 10. The primary end point was 12-month HG recurrence-free survival (RFS). All patients who received at least one dose were included in efficacy and safety analyses. Results Forty patients received rAd-IFNα/Syn3 (1 × 10(11) vp/mL, n = 21; 3 × 10(11) vp/mL, n = 19) between November 5, 2012, and April 8, 2015. Fourteen patients (35.0%; 90% CI, 22.6% to 49.2%) remained free of HG recurrence 12 months after initial treatment. Comparable 12-month HG RFS was noted for both doses. Of these 14 patients, two experienced recurrence at 21 and 28 months, respectively, after treatment initiation, and one died as a result of an upper tract tumor at 17 months without a recurrence. rAd-IFNα/Syn3 was well tolerated; no grade four or five adverse events (AEs) occurred, and no patient discontinued treatment because of an adverse event. The most frequently reported drug-related AEs were micturition urgency (n = 16; 40%), dysuria (n = 16; 40%), fatigue (n = 13; 32.5%), pollakiuria (n = 11; 28%), and hematuria and nocturia (n = 10 each; 25%). Conclusion rAd-IFNα/Syn3 was well tolerated. It demonstrated promising efficacy for patients with HG NMIBC after BCG therapy who were unable or unwilling to undergo radical cystectomy

    A Clinician\u27s Guide to Next Generation Imaging in Patients With Advanced Prostate Cancer (RADAR III).

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    PURPOSE: The advanced prostate cancer therapeutic landscape has changed dramatically in the last several years, resulting in improved overall survival of patients with castration naïve and castration resistant disease. The evolution and development of novel next generation imaging techniques will affect diagnostic and therapeutic decision making. Clinicians must navigate when and which next generation imaging techniques to use and how to adjust treatment strategies based on the results, often in the absence of correlative therapeutic data. Therefore, guidance is needed based on best available information and current clinical experience. MATERIALS AND METHODS: The RADAR (Radiographic Assessments for Detection of Advanced Recurrence) III Group convened to offer guidance on the use of next generation imaging to stage prostate cancer based on available data and clinical experience. The group also discussed the potential impact of next generation imaging on treatment options based on earlier detection of disease. RESULTS: The group unanimously agreed that progression to metastatic disease is a seminal event for patient treatment. Next generation imaging techniques are able to detect previously undetectable metastases, which could redefine the phases of prostate cancer progression. Thus, earlier systemic or locally directed treatment may positively alter patient outcomes. CONCLUSIONS: The RADAR III Group recommends next generation imaging techniques in select patients in whom disease progression is suspected based on laboratory (biomarker) values, comorbidities and symptoms. Currently 18F-fluciclovine and 68Ga prostate specific membrane antigen positron emission tomography/computerized tomography are the next generation imaging agents with a favorable combination of availability, specificity and sensitivity. There is ongoing research of additional next generation imaging technologies, which may offer improved diagnostic accuracy and therapeutic options. As next generation imaging techniques evolve and presumably result in improved global accessibility, clinician ability to detect micrometastases may be enhanced for decision making and patient outcomes

    Differential activity in Heschl's gyrus between deaf and hearing individuals is due to auditory deprivation rather than language modality

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    Sensory cortices undergo crossmodal reorganisation as a consequence of sensory deprivation. Congenital deafness in humans represents a particular case with respect to other types of sensory deprivation, because cortical reorganisation is not only a consequence of auditory deprivation, but also of language-driven mechanisms. Visual crossmodal plasticity has been found in secondary auditory cortices of deaf individuals, but it is still unclear if reorganisation also takes place in primary auditory areas, and how this relates to language modality and auditory deprivation.  Here, we dissociated the effects of language modality and auditory deprivation on crossmodal plasticity in Heschl's gyrus as a whole, and in cytoarchitectonic region Te1.0 (likely to contain the core auditory cortex). Using fMRI, we measured the BOLD response to viewing sign language in congenitally or early deaf individuals with and without sign language knowledge, and in hearing controls.  Results show that differences between hearing and deaf individuals are due to a reduction in activation caused by visual stimulation in the hearing group, which is more significant in Te1.0 than in Heschl's gyrus as a whole. Furthermore, differences between deaf and hearing groups are due to auditory deprivation, and there is no evidence that the modality of language used by deaf individuals contributes to crossmodal plasticity in Heschl's gyrus

    Rationale and design: telepsychology service delivery for depressed elderly veterans

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    <p>Abstract</p> <p>Background</p> <p>Older adults who live in rural areas experience significant disparities in health status and access to mental health care. "Telepsychology," (also referred to as "telepsychiatry," or "telemental health") represents a potential strategy towards addressing this longstanding problem. Older adults may benefit from telepsychology due to its: (1) utility to address existing problematic access to care for rural residents; (2) capacity to reduce stigma associated with traditional mental health care; and (3) utility to overcome significant age-related problems in ambulation and transportation. Moreover, preliminary evidence indicates that telepsychiatry programs are often less expensive for patients, and reduce travel time, travel costs, and time off from work. Thus, telepsychology may provide a cost-efficient solution to access-to-care problems in rural areas.</p> <p>Methods</p> <p>We describe an ongoing four-year prospective, randomized clinical trial comparing the effectiveness of an empirically supported treatment for major depressive disorder, Behavioral Activation, delivered either via in-home videoconferencing technology ("Telepsychology") or traditional face-to-face services ("Same-Room"). Our hypothesis is that in-homeTelepsychology service delivery will be equally effective as the traditional mode (Same-Room). Two-hundred twenty-four (224) male and female elderly participants will be administered protocol-driven individual Behavioral Activation therapy for depression over an 8-week period; and subjects will be followed for 12-months to ascertain longer-term effects of the treatment on three outcomes domains: (1) clinical outcomes (symptom severity, social functioning); (2) process variables (patient satisfaction, treatment credibility, attendance, adherence, dropout); and (3) economic outcomes (cost and resource use).</p> <p>Discussion</p> <p>Results from the proposed study will provide important insight into whether telepsychology service delivery is as effective as the traditional mode of service delivery, defined in terms of clinical, process, and economic outcomes, for elderly patients with depression residing in rural areas without adequate access to mental health services.</p> <p>Trial registration</p> <p>National Institutes of Health Clinical Trials Registry (ClinicalTrials.gov identifier# NCT00324701).</p
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